Abstract: The curves of apparent resistivity obtained from Magnetotelluric Sounding are greatly distorted by the lateral inhomogeneity of surficial structures. In order to delineate clearly the effects of inhomogeneity,in this study,the finite element method has been applied to simulate several structural patterns with lateral inhomogeneity and their effects on the response of Magnetotelluric Sounding. The results show that the effects of lateral inhomogeneity in the shallow layers are significant.

Key words: Lateral inhomogeneity, Apparent resistivity distortion, electromagnetic response, E-polarization, H-polarization

摘要： 大地电磁测深结果受表层构造横向不均匀性的影响,其视电阻率曲线会发生畸变。为了分析表层构造横向不均匀性对测深曲线的影响,本文采用有限单元方法对几种野外常见的表层横向不均匀构造进行了模拟计算。研究结果表明,表层构造的横向不均匀性对于测深曲线的影响是严重的。

关键词: 横向不均匀性, 视电阻率, 畸变, 电磁响应, E极化, H极化